Study of optical drive under two-photon optical data storage

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[Need to modify: copied from thesis Robust and Fault Tolerant Control of CD-players]
In 1972 Philips announced a technique to store data on an optical disc. First in 1981 Philips and Sony proposed the Compact Disc Digital Audio standard (CD-DA) which was coded in the so-called Red Book [Philips and Sony Corporation, 1991]. The development of this technique revolutionized the audio world by introducing truly digital technology for the first time. It was in the year 1982 that Philips and Sony launched the first players and discs on the market. The CD became the music carrier of choice by 1991, when sales exceeded those of audio-cassettes.
Another widely available optical disc technology is the Digital Video/Versatile Disc, abbreviated as DVD. While a CD holds either 650[MB] or 700[MB] of data, a DVD can hold up to 25 times more. There is even another type of optical discs, the so-called high capacity optical discs, which are characterized by offering the user storage capacities typically in the range from 20[GB] to 50[GB], (approximately between 30 to 75 times more data than a CD). At this writing, four high capacity optical discs have been announced so far: the Blu-ray disc (BRD) [Hitachi et al., 2002], the advanced optical disc [Toshiba and NEC, 2002], the Blue-HD (High Density) disc [OES and AOSRA, 2002] and the HD-DVD-9 disc [Bros, 2002]. All are in principle rewritable discs, although ROM versions are being discussed.
Since the first mass replication moulded CDs were introduced on the market a confusing number of optical disc formats have been developed giving the consumer not only the possibility to read data but also to record and erase as desired. The numerous standards and formats of optical discs can be divided in three g...

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...s correction code is used in DVDs, called Reed-Solomon (RS) product code, capable of correcting a burst length of approximately 6[mm]. The deinterleave process is achieved by writing sequentially into a data buffer and reading out by means of a sequencer. The speed of the disc motor is unimportant and the system drives the spindle at whatever speed is necessary so that the data buffer neither underflows nor overflows. The size of the data buffer is a compromise between economical costs and resistance to burst errors.

Why optical discs drive?
In recent years, optical disk drive has become one of major data storage devices in auxiliary memory devices and AV systems. The reasons for this popularity are its short access time compared with that of magnetic tape drive, exchangeability of disks, and almost unlimited lifetime [New Fine Seek Control for Optical Disk Drives]

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